MAGNETEC. Advanced softmagnetic materials for electromagnetic compatibility EMC

Transcription

1 Advanced softmagnetic materials for electromagnetic compatibility EMC MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 1/35

2 - EMC/EMI basics - mains filters and current compensated chokes - comparison: nano and ferrite cores - production process of nanocrystalline cores Content of presentation MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 2/35

3 electromagnetical compatibility (EMC) can be described as a - required - state: MAGNETEC the ability of a device, to work satisfactory in its electromagnetical surrounding, without generating disturbing noise, which could be unacceptable for other devices. (EMV-Richtlinie 89/336/EWG bzw. EMVG) Currently, the global electromagnetical background noise level doubles every three years! 1) EMC basics: definition of EMC 1) Schaffner EMV AG MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 3/35

4 Steep du/dt switching edges of mircroprocessors or power transistors (IGBT) or pulsed currents drawn from the mains supply line of switched mode power supplies (SMPS) are the main reason for the unwanted emsissions of discrete or continuous RF energy. Examples: - digital telecommunication equipment (ISDN, GSM) - electronical power supplies for lightening applications - any kind of voltage converter using SMPS technology - variable speed drives - white goods with microprocessors and variable speed drives EMC basics: sources of RF noise emissions MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 4/35

5 230Vmains ~ rectifier smoothening Big 50 Hztrafo DCoutput Hz-mains adaptor - no RF- noise level but huge & heavy 230Vmains ~ small 50 khztrafo EMIfilter switch rectifier smooth. DCoutput + - SMPS - EMI filter required, compact, light weight, highly efficient Comparison: 50Hz vs. switched mode power supply MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 5/35

6 50-Hz-technology example: adaptor P s = 6 VA (12V / 0,5A) m = 440g η = 38 % SMPS example: notebook P s = 30VA (15V / 2A) m = 220g η up to 95 % SMPS technology: significant reduction of size and weight MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 6/35

7 radiated noise distribution capacitive and inductive coupling MAGNETEC conducted noise distribution RF source emission radiation Radiation E-field H-field I s U s RF drain immunity noise current noise voltage possible ways of distribution of RF noise EMC basics: scenario MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 7/35

8 variable speed drive (inverter) = source e.g. ISA ~ rectifier DC dc-link DC PWM inverter ~ asynchronous motor control circuit Unoise [dbµv] Unoise [dbµv] frequency [khz] frequency [khz] rf variable voltage & frequency EMC basics: inverter drive as rf-noise source MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 8/35

9 typical voltage and harmonics in a variable speed drive (inverter) used in many future PowerNet systems. Those unwanted rf-signals are distributed over all connected wiring systems t t = 50ms/unit T = 250ms 250ms fundamental wave 4 khz harmonics khz khz [f] [f] EMC basics: sources of RF noise emissions MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 9/35

10 100 ~ amount % 50 conducted emission filter radiated emission shielding 0 1 khz MHz GHz LW MW SW FM frequency f typical distribution of emitted energy as a function of frequency EMC basics: ways of distribution of RF noise MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 10/35

11 Quasi Peak voltage U [dbµv] class A industrial class B domestic 1: : : khz frequency 30 MHz noise level-limits of EN (common mode, conducted, 50Ω-system) EMC basics: RF noise level limits MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 11/35

12 reference ground test device artifical mains test receiver wooden table all values in cm EMC basics: measurement setup for RF noise MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 12/35

13 Us [dbµv] , f [MHz] poor filtering, limits of EN55011, class B are exceeded Us [dbµv] appropriate filtering, limits of EN55011, class B are met EMC basics: real noise level spectrum (quasi-peak) MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 13/35

14 -Increasing number of unwanted RF-noise sources resulting in a continuous increase of background level - regulations will be getting more stringent - regulations will be defined in new - new regulations to come - new noise sources will come - contious increase of costs for filtering measures - global introduction of emc regulations EMC basics: future trends and outlook MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 14/35

15 L 1 Filter MAGNETEC 240V mains N PE C x1 L C y2 C x2 C y2 R load C xn C yn L R X-capacitor Y-capacitor current compensated choke discharge resistor basic circuitry of a EMI mains filter EMC basics: mains filter MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 15/35

16 EMI filters are commonly desinged as reflecting low-pass-filters ausgelegt, this means, they work according to the principle of rf-mismatch. Thus, a part of the high-frequency currents are deviated the other part will be aborped e.g. in form of core losses and other mechanisms. differential mode noise f < 500kHz source of noise C x1 L streu C x1 C y2 C y2 noise drain Propagation of noise currents common mode noise f > 500kHz source of noise C x1 L N C x2 C y2 C y2 noise drain EMC basics: working principle of mains filters MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 16/35

17 measuring generator (150kHz-30MHz) 1:1 1:1 measuring receiver (selective voltmeter) 50 Ω test item (filter) 50 Ω U 1 U 2 α e = 20 log U 1 2 U 2 [db] conforming test setup of attenuation level α e EMC basics: setup of attenuation level measurement MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 17/35

18 RF current H load = 0 H RF 0 single phase version load current working principle of a current compensated choke for attenuation of common mode RF noise three-phase version EMC basics: principle of common mode chokes MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 18/35

19 main requirements on a EMC filter choke: high impedance (f = 150 khz to 30 MHz) Z(f) = ωl(f) = 2πf L(f) L(f) = A L n 2 mit A L = µ 0 µ r (f) A fe /l f number of turns permeability! iron cross section EMC basics: choice of softmagnetic material MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 19/35

20 Induktion B Bs Br Hc Hs Feldstärke H Bs: saturation lux density (high!) Br: remanence (low!) Hc: coercitivity field strength (low!) Hs: saturation field strength (high!) Characteristics of softnagnetic alloys: Hysteresis loop MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 20/35

21 -1987: patent for a completely new softmagnetic material with excellent properties by Yoshizawa, Oguma and Yamauchi (Hitachi, Japan) alloy composition: Fe 73 Cu 1 Nb 3 Si 16 B 7 production process: rapid solidification material structure: nanocrystalline; i.e. grain size 15 nm : markt launch by VACUUMSCHMELZE (VITROPERM ) and HITACHI Metals (FINEMET ) - since 1995: introduction into several industrial applications of power electronics and telecommunication : 3. Source : MAGNETEC (NANOPERM ) History of nanocrystalline alloys MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 21/35

22 Alloy Permeability µ r (10 / 100kHz) Saturation induction Bs [T] (25 / 100 C) Curie-temp. Tc [ C] max. working temp. T max [ C] Ferrite 3E / ,38 / 0,21 > Ferrite T / ,38 / 0,23 > NANOPERM / } / ,2 / 1, (180) / NANOPERM vs. Ferrit: - permeability - up to a factor of 10 (!) - saturation induction - factor 3 - working temperature range - up to 180 C - disadvantage: price ~ factor 1,5-2 (functional value) advanced, smaller and lighter components Comparison of materials MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 22/35

23 1,5 1,0 NANOPERM µ = µ = ,5 B [T] 0-0,5 Ferrite T 38 µ = ,0 f = 1 Hz -1, H [ma/cm] hysteresis loops, saturation field as a function of permeability level Comparison of materials MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 23/35

24 10kHz/3mA/cm NANOPERM Ferrite max. max. for for Ferrite: about 120 C MAGNETEC T [ C] permeability as as a function of of temperature Comparison of materials MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 24/35

25 saturation induction Bsat [T] 1,4 1,2 1 0,8 0,6 0,4 0,2 0 Ferrite T38 N67 NANOPERM max. max. for for Ferrite: about 120 C T [ C] saturation flux flux density as as a function of of temperature T Comparison of materials MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 25/35

26 60 50 NANOPERM attenuation level [db] Ferrite improved attenuation below khz khz 0,01 0,1 1,0 10,0 100,0 frequency f (MHz) typical impedance curve at at same core core geometry Ø=30mm, 22 22turns Comparison of materials MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 26/35

27 20 impedance Z [k W] 12 4 volume reduction > 50% 50% NANOPERM = 40 mm Ferrite = 63 mm f [khz] typical impedance curve for for different core core geometries Comparison of materials MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 27/35

28 120 MAGNETEC noise level [dbµv] Ferrite Ø: 63mm, 3x22 turns, m = 380g NANOPERM Ø: 40 mm, 3x32 turns, m = 94g 0 0, frequency f [MHz] achieving more stringent noise limits even at a smaller build volume Comparison of materials MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 28/35

29 NANOPERM-choke I N = 3 x 60 C L N = 3 x 1,6 10kHz m = 120g volume reduction 60% 60% weight reduction % MAGNETEC Ferrite-choke I N = 3 x 40 C L N = 3 x 1,3 10kHz m = 350g 59 mm 73 mm 25 mm 39 mm Comparison of build volume Nano/Ferrite Chokes MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 29/35

30 ribbon thickness ~20µm AMT amorphous ribbon melt, T= 1200 C ceramiknozzle Cu-wheel, T = 20 C v = 100km/h principle of production process of rapidly quenched ribbons MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 30/35

31 cutting of ribbons with high precision knives MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 31/35

32 automatic winding process of tape wound cores MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 32/35

33 300 cm 60 cm furnace and batch of cores for magnetic-field treatment MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 33/35

34 protective epoxy coating of tape wound cores MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 34/35

35 tape wound cores from mm single phase EMC chokes up to I = 60A 160 mm three phase EMC chokes up to I = 200A available nano products core and choke types MAGNETEC GmbH, Langenselbold 05/2002 Dr. Fe 35/35